Automatic transmissions require at least one hydraulic fluid supply system for the hydraulic fluid supply of transmission elements such as shift elements or the like. For the hydraulic fluid supply of the system, one hydraulic pump controlled on the engine side and one hydraulic pump controlled on the transmission output side or on the gear set side are typically provided. The provided hydraulic pumps may be allocated to separate hydraulic fluid circuits or systems, such that the hydraulic pump controlled on the engine side is used to generate system pressure and the hydraulic pump controlled on the gear set side is used to cool the gear set. Thus, the hydraulic pumps operate structurally separate oil circuits or hydraulic fluid supply circuits, and thus are not able to support each other. Allocating the hydraulic pumps to a common hydraulic fluid supply circuit is also known.
In a disadvantageous manner, it has been found that, with certain operating modes of the motor vehicle, such a hydraulic fluid supply, for example, does not make available system pressure for actuating shift elements, such that, during predetermined operating modes, due to a lack of system pressure, gear tracking or clutch filling (for example) is not possible.